kernel/: convert cpu notifier to return encapsulate errno value

By the previous modification, the cpu notifier can return encapsulate
errno value.  This converts the cpu notifiers for kernel/*.c

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --cc kernel/padata.c
Simple merge

diff --cc kernel/profile.c
Simple merge

diff --cc kernel/relay.c
Simple merge

diff --cc kernel/smp.c
Simple merge

diff --cc kernel/softirq.c
Simple merge

diff --cc kernel/timer.c
Simple merge

diff --cc kernel/workqueue.c
Simple merge